Hydrogen is commonly used as a cooling fluid. Some electrical power generators communicate hydrogen through their windings to remove thermal energy from the generator. Hydrogen is particularly useful for this application due to its high heat capacity and relatively low density. Using hydrogen as a cooling fluid is particularly prevalent in large generators, such as generators configured to provide more than 150 megawatts of power.
Some devices that utilize hydrogen as a cooling fluid receive the hydrogen directly from a stored hydrogen supply, such a storage tank. The stored hydrogen supply must be periodically refilled, which is costly and inefficient. The stored hydrogen onsite is also a safety concern. The flow of hydrogen from the stored hydrogen supply can also carry moisture into the generator, particularly when the hydrogen supply is not optimized to meet the demand for hydrogen. The moisture can crack retaining rings and other components in the generator. Some electrical power generators receive a flow of hydrogen directly from an electrolyzer rather than a hydrogen supply. The electrolyzer produces hydrogen as needed. As known, electrolyzers are costly and require significant capital cost to implement. For all of these reasons, it is desirable to reduce the amount of hydrogen required while still supplying hydrogen having an appropriate pressure, temperature, and purity to efficiently cool the electric power generator.